ST. LOUIS -- When the Boston Bruins go on the power play, they are thinking one thing: Make the opponent pay for taking a penalty.
"That's the first thing we tell each other," Bruins forward David Pastrnak said.
The Bruins were lethally efficient in doing that in their 7-2 victory against the St. Louis Blues in Game 3 of the Stanley Cup Final at Enterprise Center on Saturday.
Boston went 4-for-4 on the power play on its way to taking a 2-1 lead in the best-of-7 series. Game 4 is in St. Louis on Monday (8 p.m. ET: NBC, CBC, SN, TVAS).
The Bruins needed four total shots to score their four power-play goals and didn't require more than 51 seconds to convert on any of their man-advantage opportunities.
Video: BOS@STL, Gm3: Bruins score four PPGs on four shots
It started with defenseman Torey Krug, who had the primary assist on three of the power-play goals and scored the other one. Although the Bruins' top line of Brad Marchand, Patrice Bergeron and Pastrnak has yet to produce a 5-on-5 goal in the series, it was more dangerous Saturday.
Bergeron and Pastrnak scored power-play goals. Bergeron had a goal and two assists, all on the power play. Marcus Johansson also scored on the power play.
"I think it was just a night where everything went our way," said Krug, whose four points set a Bruins Cup Final record.
A lot has been going the Bruins' way on the power play in the Stanley Cup Playoffs.
They are 6-for-14 (42.9 percent) in the Final, 13-for-29 (44.8 percent) over the past two rounds and an NHL-best 23-for-64 (35.9 percent) for the playoffs. By comparison, the Blues are 1-for-10 on the power play in the Final, including 1-for-5 in Game 3.
"I think we just have a lot of different abilities and talents out there," said Marchand, who assisted on Krug's power-play goal. "We've been together for a while now, so we're comfortable with communicating and trying to look for different things. With Torey back there making the plays that he's making, we get lucky sometimes."
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Despite their power-play success in the playoffs, the Bruins were unhappy with their execution in the first two games of the Final. Boston went 2-for-10 on the man-advantage in splitting the first two games against St. Louis with each of the goals coming off zone-entry plays.
After reviewing some video, a decent portion of the Bruins practice on Friday was dedicated to working on the power play.
"We've really focused on entries, scoring, worked against Carolina," Bruins coach Bruce Cassidy said. "We try to exploit certain areas if we can. But O-zone, I thought we forced a lot of plays, didn't recover pucks well, we didn't have the support."
At one point during the practice, David Backes, who was subbing on the first unit while Bergeron took a maintenance day, scored on a deflection play similar to the one that Bergeron scored on to open the scoring 10:47 into the first period Saturday.
Krug took a wrist shot from the right point that Bergeron, who was stationed in the "bumper" spot at the inner rim of the right circle, tipped past goalie Jordan Binnington. That came 21 seconds into the Bruins' first power play, setting the tone for the night.
"I think we were taking what's there," said Bergeron, whose seven power-play goals are most in the playoffs. "I think maybe earlier we were forcing plays a little too much and tonight we put the puck on net and when you do that good things happen."
Video: BOS@STL, Gm3: Krug on setting B's record, Game 3 win
Pastrnak scored the Bruins' second power-play goal to increase their lead to 4-0 at 41 seconds of the second period. Krug was at the left point on that one and fed Pastrnak to the left of the net before he lifted a backhand over Binnington's right pad.
After Ivan Barbashev cut Boston's lead to 4-1 at 11:05 of the second, the Bruins struck on the power play again with Krug taking a right point shot that deflected in off the stick of Blues defenseman Jay Bouwmeester in front at 12:12 - 31 seconds into Colton Parayko's high-sticking minor. That ended Binnington's night after he allowed five goals on 19 shots.
"We tried to be more decisive and assertive getting pucks to the net after one or two passes," Krug said. "The fact that we knew that someone was going to shoot the puck off of one or two passes allowed our guys to just get to the net in front of the goaltender's eyes and then recover the puck if there's a rebound to be had. So [it was] assertiveness and good decision-making and our skill guys came through."
The Bruins' power-play prowess has mostly overshadowed the effectiveness of their penalty kill, which had killed 21 straight before Parayko's power-play goal 5:24 into the third period that cut it 5-2. And getting Bergeron's line going could spell bad news for the Blues.
"We found our game and we executed and stayed close to each other in their zone and that's about it," Bergeron said.